I’m not entirely sure what is your question, but currently there are 3~9 scenes, depending if you count the variations. You have 3 scenes for the Wharf Roach, 2 for the Parasite Beasts and 3 for the Parasite Worm.
For the normal cases, different scenes trigger based on lewdness level and if your are defeated, fail to escape or caught in battle, depends on the enemies you’re facing. The Parasite Worm scenes trigger differently according to the sleep choices and number of scenes already played/skipped.